The present invention relates to a plastic clad metal laminate suitable for use in forming heat transfer partitions for apparatus capable of simultaneous heat and mass transfer More particularly it relates to such a plastic clad metal laminate usefully employed in the construction of an apparatus for cooling and conditioning air used in habitable dwellings, i.e., an air conditioner.
In U.S. Pat. No. 4,832,115 to Walter F. Albers, et al. there is disclosed an apparatus for simultaneous heat and mass transfer In particular there is disclosed an apparatus for changing at least one selected property of two wetting substances, said apparatus comprising one or more heat transfer partitions as well as associated means for moving air, wetting means, etc. In the embodiment of the foregoing apparatus particularly adapted for use in conditioning air for habitable dwellings the aforementioned heat transfer partitions generally describe a compartment and may be subjected to heating or cooling by contacting with a heat transfer medium particularly brine or salt solution. In the aforementioned patent at column 2, lines 49-51 it is disclosed that heat transfer partitions can be made of inexpensive plastic film or metal foils.
Disadvantageously when the aforementioned plastic film or metal foils are employed as a heat transfer partition in an apparatus for simultaneous heat and mass transfer, particularly one involving the movement of air in contact with such heat transfer partitions, plastic film or metal foils have proven unacceptable for use. In particular metal foils usually possess insufficient resistance to corrosive effects of the brine or water employed for heat transfer means. Plastic films on the other hand although noncorrosive have higher heat capacities, and lower thermal conductivities compared to metals. They have proven unacceptable in through that when prepared in a suitably thin section necessary for adequate heat conduction through the heat transfer partition, the plastic has insufficient strength to resist damage or vibration due to the motion of air past the heat transfer partition. In addition, in an embodiment whereby increased surface area is provided by folding the heat transfer partition in parallel folds or pleats, plastic film is difficult to form into permanent creases.
A further difficulty with the use of inexpensive plastic film is the fact that generally insufficient heat transfer from the wetting substance results due to the fact that many thermoplastic resin film surfaces are hydrophobic. This fact prevents the water or brine solution from forming a continuous wetting surface on the heat transfer partition to maximize for improved heat conduction.
Lastly it is desirable in the construction of a suitable apparatus for simultaneous heat and mass transfer to prevent formation of microbiological growth such as fungal or bacterial growth on the heat transfer partitions. Not only does such microbial growth inhibit heat transfer through the heat transfer partition but certain microbiological organisms are also considered to be injurious to human health, such as Legionnaires Bacterium which has been found to be capable of growth in wet environments involving mist and recycling of water.
Thus it would be desirable if there were provided a material suitable for forming into heat transfer partitions for use in apparatus for simultaneous heat and mass transfer which is capable of efficient transfer of heat therethrough and is resistant to vibration or damage caused by the motion of air or liquid at high velocity, which additionally is easily fabricated or formed into pleated or folded sections having increased surface area for contact with the moving air or liquid heat transfer medium.
In addition it would be desirable if there were provided a material suitable for forming into heat transfer partitions that has a surface wettability to achieve rapid and thorough dispersion of aqueous heat transfer solutions or water in order to achieve efficient heat transfer.
Finally it would be highly desirable that this material be corrosion resistant to brine and aqueous medium.